Getting 500 error when viewing some projects after upgrade to 8.11

I just upgraded our GitLab server to 8.11 (using the Omnibus package on Centos 6) and now when accessing some projects get the following error:

Completed 500 Internal Server Error in 184ms (ActiveRecord: 16.7ms)

ActionView::Template::Error (missing attribute: developers_can_push):
    43:       %li
    44:         = link_to 'Contribution guide', contribution_guide_path(@project)
    45:
    46:     - if @repository.gitlab_ci_yml
    47:       %li
    48:         = link_to 'CI configuration', ci_configuration_path(@project)
    49:
  app/models/project.rb:862:in `each'
  app/models/project.rb:862:in `any?'
  app/models/project.rb:862:in `developers_can_push_to_protected_branch?'
  lib/gitlab/user_access.rb:32:in `can_push_to_branch?'
  app/helpers/branches_helper.rb:26:in `can_push_branch?'
  app/views/projects/show.html.haml:46:in `_app_views_projects_show_html_haml__3065635067789669423_160625420'
  app/controllers/projects_controller.rb:111:in `block (2 levels) in show'
  app/controllers/projects_controller.rb:103:in `show'
  lib/gitlab/middleware/go.rb:16:in `call'

Similarly, when I try to access the Admin area, I get this:

Completed 500 Internal Server Error in 71ms (ActiveRecord: 10.2ms)

ActionView::Template::Error (undefined method `version' for Gitlab::Workhorse:Class):
    82:         %p
    83:           GitLab Workhorse
    84:           %span.pull-right
    85:             = Gitlab::Workhorse.version
    86:         %p
    87:           GitLab API
    88:           %span.pull-right
  app/views/admin/dashboard/index.html.haml:85:in `_app_views_admin_dashboard_index_html_haml__1872664094672610036_210458540'
  lib/gitlab/middleware/go.rb:16:in `call'

I attempted the upgrade (from version 8.10) in the usual fashion:

$ yum update gitlab-ce -y && gitlab-ctl reconfigure